Abstract: A programming device for a programmable controller comprising a unit specification information table in which specifications of a functional unit are set, a unit configuration table in which combinations of functional units are set, and a program preparing means for assisting input of a program for a programmable controller according to various types of information in said unit specification information table and the unit configuration information table.

Abstract: A data transmission apparatus and a communication management method for transmitting data from task program devices to peripheral devices over a plurality of communication paths. The apparatus includes a communication path management table for storing management data corresponding to each communication path established between the task program devices and the peripheral devices, a communication path management device for retrieving the management data from the communication path management table to select a communication path in response to a request from a requesting task program device to establish a communication path to a specified peripheral device, and a communication protocol processor for controlling communications between the task program devices and peripheral devices by establishing the selected communication path between the requesting task program device and the specified peripheral device.